<?php
/*
 * Resize images dynamically using wp built in functions
 * Victor Teixeira
 *
 * php 5.2+
 *
 * Exemplo de uso:
 * 
 * <?php 
 * $thumb = get_post_thumbnail_id(); 
 * $image = vt_resize($thumb, '', 140, 110, true);
 * ?>
 * <img src="<?php echo $image[url]; ?>" width="<?php echo $image[width]; ?>" height="<?php echo $image[height]; ?>" />
 *
 * @param int $attach_id
 * @param string $img_url
 * @param int $width
 * @param int $height
 * @param bool $crop
 * @return array
 */

if(!function_exists('vt_resize')) {
	
	function vt_resize($attach_id = null, $img_url = null, $width, $height, $crop = false) {
		
			// this is an attachment, so we have the ID
			if($attach_id) {
			
				$image_src = wp_get_attachment_image_src($attach_id, 'full');
				$file_path = get_attached_file($attach_id);
			
			// this is not an attachment, let's use the image url
			} elseif($img_url) {
	
				if(!preg_match("/http:/", $img_url)) { $img_url = site_url().'/'.$img_url; }
				$file_path = parse_url($img_url);
				$file_path = $_SERVER['DOCUMENT_ROOT'] . $file_path['path'];
				
			// Look for Multisite Path
			if(file_exists($file_path) === false){
				global $blog_id;
				$file_path = parse_url($img_url);
				if (preg_match("/files/", $file_path['path'])) {
					$path = explode('/',$file_path['path']);
					foreach($path as $k=>$v){
						if($v == 'files'){
							$path[$k-1] = '/wp-content/blogs.dir/'.$blog_id;
							}
						}
					$path = implode('/',$path);
					}
				$file_path = $_SERVER['DOCUMENT_ROOT'].$path;
				}
				//$file_path = ltrim($file_path['path'], '/');
				//$file_path = rtrim(ABSPATH, '/').$file_path['path'];
				
					$orig_size = getimagesize($file_path);
				
					$image_src[0] = $img_url;
					$image_src[1] = $orig_size[0];
					$image_src[2] = $orig_size[1];
				}
			
			$file_info = pathinfo($file_path);

			// check if file exists
			$base_file = $file_info['dirname'].'/'.$file_info['filename'].'.'.$file_info['extension'];
			if (!file_exists($base_file))
			return;

			$extension = '.'. $file_info['extension'];
		
			// the image path without the extension
			$no_ext_path = $file_info['dirname'].'/'.$file_info['filename'];
		
			$cropped_img_path = $no_ext_path.'-'.$width.'x'.$height.$extension;
		
			// checking if the file size is larger than the target size
			// if it is smaller or the same size, stop right here and return
			if(($image_src[1] > $width && $width > 0) || ($image_src[2] > $height && $height > 0)) {
		
				// the file is larger, check if the resized version already exists (for $crop = true but will also work for $crop = false if the sizes match)
				if(file_exists($cropped_img_path)) {
		
					$cropped_img_url = str_replace(basename($image_src[0]), basename($cropped_img_path), $image_src[0]);
					
					$vt_image = array (
						'url' => $cropped_img_url,
						'width' => $width,
						'height' => $height
					);
					
					return $vt_image;
				}
		
				// $crop = false
				if($crop == false) {
				
					// calculate the size proportionaly
					$proportional_size = wp_constrain_dimensions($image_src[1], $image_src[2], $width, $height);
					$resized_img_path = $no_ext_path.'-'.$proportional_size[0].'x'.$proportional_size[1].$extension;			
		
					// checking if the file already exists
					if(file_exists($resized_img_path)) {
					
						$resized_img_url = str_replace(basename($image_src[0]), basename($resized_img_path), $image_src[0]);
		
						$vt_image = array (
							'url' => $resized_img_url,
							'width' => $proportional_size[0],
							'height' => $proportional_size[1]
						);
						
						return $vt_image;
					}
				}
		
				// check if image width is smaller than set width
				$img_size = getimagesize($file_path);
				if ($img_size[0] <= $width) $width = $img_size[0];

				// Check if GD Library installed
				if (!function_exists ('imagecreatetruecolor')) {
					echo 'GD Library Error: imagecreatetruecolor does not exist - please contact your webhost and ask them to install the GD library';
					return;
				}
			
				// no cache files - let's finally resize it
				// .............................................................
	
				// first, make sure the directory is writable.
				if (is_writable($file_info['dirname'].'/')) {
					// it's writable, let's do some resizing!
					$new_img_path = image_resize($file_path, $width, $height, $crop);
					$new_img_size = getimagesize($new_img_path);
					$new_img = str_replace(basename($image_src[0]), basename($new_img_path), $image_src[0]);
				} else {
					// nope, directory isn't writable. return the original file info
					$new_img = $img_url;
					$new_img_size[0] = $width;
					$new_img_size[1] = $height;
				}
		
				// set image data for output
				$vt_image = array (
					'url' => $new_img,
					'width' => $new_img_size[0],
					'height' => $new_img_size[1]
				);
				
				return $vt_image;
			}
		
			// default output - without resizing
			$vt_image = array (
				'url' => $image_src[0],
				'width' => $width,
				'height' => $height
			);
			
			return $vt_image;
		}
} 

?>